1218 THE VOYAGE OF H.M.S. CHALLENGER. 



singly or in pairs along the surface ; the hand, a narrow oval, as long as the wrist but 

 not so wide, with six groups or rows of long pectinate spines adjacent to the front 

 margin ; the hind margin a little serrate, with a few long slender spines and some 

 spaced palmar spines ; at a little distance from the hind margin are some slender 

 feathered spines, the groups being close set near what may be reckoned as the palm- 

 border, of which the portion nearest the hinge is almost straight or tending to concave ; 

 the finger is slender, about half the length of the hand, the outer margin convex, with 

 a long dorsal cilium close to the hinge, the inner margin nearly straight as far as the 

 nail and set with several setules, the nail about one-third the length of the basal part of 

 the finger. 



Second Gnathopods longer than the first, but with a narrower wrist. The side-plates 

 with the breadth and depth equal. The first joint longer than in the preceding pair, but 

 scarcely so wide ; the second and third joints narrower than in the preceding pair, the 

 third with fewer spines and the apex acute ; the wrist very elongate, yet scarcely so long 

 as the first joint, its greatest width much nearer the distal end than the base, with spines 

 at seven points of the slightly convex front margin, and five or six large groups of long 

 pectinate spines on the serrate hind margin, besides slighter spines on the surface, and 

 on the oblique distal part of the hind margin ; the hand in general form is a long narrow 

 oval, shorter than the wrist, but longer than the hand of the first gnathopods, which it 

 much resembles in armature, though the front margin is more lightly spined, the hind 

 margin is not serrate or scarcely so, and the palm is pretty distinctly marked by a 

 shallow concavity, over which the finger curves, leaving a narrow elliptical space between 

 its inner margin and the palm ; the finger resembles that of the preceding pair, except in 

 having its inner margin more concave. 



First Pcrseopods. — The side-plates like the preceding pair. The marsupial plates 

 narrow, shorter than the elongate first joint of the limb. 



Second Perseopods. — The side-plates rather broader above than in the preceding pair. 

 The first joint long and narrow, with some slender spines at intervals along the hind 

 margin, and some spinules on the front ; the second joint quite short, with some small 

 spines at the apex behind ; the third joint thinner than the first, but very little shorter, 

 with spines of very different lengths and spinules at seven or eight distant points of the 

 slightly concave and serrate hind margin, and at five points of the slightly convex front ; 

 the fourth joint very elongate, but thinner and shorter than the third, with spines and 

 spinules at six points behind and five in front ; the fifth joint elongate, thinner than the 

 fourth, carrying some spinules ; the length not determined, the joint being broken. 



The other perseopods were missing. One or two of the branchial vesicles were 

 observed to be broadly oval. 



Pleopods. — The peduncles long, distally produced in a small acute process which 

 seems to coalesce with the first joint of the outer ramus ; the peduncles, at least in the 



